Siloxane-oxyalkylene copolymer surfactant compositions

Abstract

Siloxane-oxyalkylene copolymer surfactants in combination with alkyl esters of fatty acids are disclosed. Alkyl esters of fatty acids are represented by the general formula Z—COO—Y where Z is a saturated or unsaturated C10-24 alkyl or alkylene group and Y is typically a C1-6 alkyl, alkylene linear or branched group. The siloxane-oxyalkylene copolymer surfactants that are typically used with the fatty esters have the general formula MDxD′yM wherein M represents (CH3)3SiO1/2 or R(CH3)2SiO1/2, D represents (CH3)2SiO2/2, D′ represents (CH3)RSiO2/2, and the value of x+y is from 50 to 220, and the ratio x/y is from 5 to 15 inclusive. In the above formulae for M and D′, R is a polyether-containing substituent. The siloxane-oxyalkylene copolymer surfactants used in conjunction with the fatty ester contains a major fraction (60-80 wt. %) of siloxane-oxyalkylene with one pendant R typically defined as CnH2nO(C2H4O)a(C3H6O)bR′ moieties having weight average molecular weights of from about 1400-2000 and wherein n is 1-4 and typically 3, the values of “a” are in the range 12-22 and typically 16-20 and the values of “b” are in the range of 12-22 and typically 16-20, R′ typically represent acyl group —C(O)CH3. The surfactant of the invention also contains a minor fraction of a siloxane-oxyalkylene copolymer (6-10 wt. %) having two pendant R typically defined as CnH2nO(C2H4O)a(C3H6O)bR′ moieties having average molecular weights of about 1000-3500 and wherein n is 1-4 and typically 3, the values of “a” are in the range 8-40 and typically 10-35 and the values of “b” are in the range of 8-40 and typically 10-35, R′ typically represent acyl group C(O)CH3.

The invention claimed is: 
     
       1. A composition comprising siloxane-oxyalkylene copolymers, at least one alkyl ester of a fatty acid comprising a methyl ester of rapeseed oil, and dipropylene glycol; wherein the siloxane-oxyalkylene copolymers have the general formula MD x D′ y M wherein M in each instance represents (CH 3 ) 3 SiO 1/2  or R(CH 3 ) 2 SiO 1/2 , D represents (CH 3 ) 2 SiO 2/2 , D′ represents (CH 3 )RSiO 2/2 , R in each instance is a polyether-containing substituent, the value of x+y is from 50 to 220, the ratio x/y is from 5 to 15 inclusive, and wherein the siloxane-oxyalkylene copolymers comprise
 a) a first siloxane-oxyalkylene copolymer with a DP in the range of 110-130, a D/D′ in the range of 9-11, and an EO/PO molar ratio in the range of 1.0-1.05; 
 b) a second siloxane-oxyalkylene copolymer with a DP in the range of 190-210, a D/D′ in the range of 6-8, and an EO/PO molar ratio in the range of 1.0-1.05; and; 
 c) a third siloxane-oxyalkylene copolymer with a DP in the range of 60-80, a D/D′ in the range of 6-8, and an EO/PO molar ratio in the range of 1.0-1.05. 
 
     
     
       2. The composition of  claim 1  wherein the siloxane-oxyalkylene copolymers include at least one siloxane-oxyalkylene copolymer comprising one pendant R moiety defined as C n H 2n O(C 2 H 4 O) a (C 3 H 6 O) b R 1  having a weight average molecular weight of from about 1400-2000 and wherein n is 1-4, the value of a is in the range of 12-22, the value of b is in the range of 12-22, and R′ is the acyl group C(O)CH 3 . 
     
     
       3. The composition of  claim 1  wherein the siloxane-oyxalkylene copolymers include at least one siloxane-oxyalkylene copolymer comprising two pendant R moieties defined as C n H 2n O(C 2 H 4 O) a (C 3 H 6 O) b R′ having a weight average molecular weight of from about 1000-3500 and wherein n is 1-4, the value of a is in the range of 8-40, the value of b is in the range of 8-40, and R′ is the acyl group C(O)CH 3 . 
     
     
       4. The composition of  claim 1  wherein the first siloxane-oxyalkylene copolymer comprises one pendant R moiety defined as C n H 2n O[C 2 H 3 (M)O] a R′, wherein M in the moiety C n H 2n O[C 2 H 3 (M)O] a R′ is H from ethylene oxide or methyl from propylene oxide, wherein the C n H 2n O[C 2 H 3 (M)O] a R′ moiety has a weight average molecular weight of from about 700-2500 and wherein n is 1-4, the value of a is in the range of 24-50, and R′ is the acyl group C(O)CH 3 . 
     
     
       5. The composition of  claim 1  wherein the second siloxane-oxyalkylene copolymer comprises two pendant R moieties, wherein the first pendant R moiety is defined as C n H 2n O[C 2 H 3 (M)O] a R′, wherein M in the moiety C n H 2n O[C 2 H 3 (M)O] a R′ is H from ethylene oxide or methyl from propylene oxide, wherein the C n H 2n O[C 2 H 3 (M)O] a R′ moiety has a weight average molecular weight of from about 700-2500 and wherein n is 1-4, the value of a is in the range of 24-50, and R′ is the acyl group C(O)CH 3 , and the second pendant R moiety is defined as —C n H 2n O(C 2 H 4 O) a R′ having a weight average molecular weight of from about 2300-3200 and wherein n is 1-4, the value of a ace is in the range of 15-20, and R′ is the acyl group C(O)CH 3 . 
     
     
       6. The composition of  claim 1  wherein the third siloxane-oxyalkylene copolymer comprises two pendant R moieties, wherein the first pendant R moiety is defined as C n H 2n O[C 2 H 3 (M)O] a R′, wherein M in the moiety C n H 2n O[C 2 H 3 (M)O] a R′ is H from ethylene oxide or methyl from propylene oxide, wherein the C n H 2n O[C 2 H 3 (M)O] a R′ moiety has a weight average molecular weight of from about 750-1800 and wherein n is 1-4, the value of a is in the range of 16-32, and R′ is the acyl group C(O)CH 3 , and the second pendant R moiety is defined as —C n H 2n O[C 2 H 3 (M)O] a R′, wherein M in the moiety C n H 2n O[C 2 H 3 (M)O] a R′ is H from ethylene oxide or methyl from propylene oxide, wherein the —C n H 2n O[C 2 H 3 (M)O] a R′ moiety has a weight average molecular weight of from about 2500-3500 and wherein n is 1-4, the value of a is in the range of 50-70, and R′ is the acyl group C(O)CH 3 . 
     
     
       7. The composition of  claim 1  further comprising at least one alkyl ester of a fatty acid represented by the general formula Z—COO—Y wherein Z is a saturated or unsaturated C 10-24  alkyl or alkylene group, and Y is a C 1-6  alkyl group, alkylene group, linear group or branched group. 
     
     
       8. The composition of  claim 1  further comprising at least one member selected from the group consisting of at least one polyol, at least one catalyst and at least one blowing agent. 
     
     
       9. A method for making a polyurethane foam comprising contacting the composition of  claim 8  with at least one isocyanate. 
     
     
       10. A polyurethane foam made by the method of  claim 9 . 
     
     
       11. The composition of  claim 1  wherein the first siloxane-oxyalkylene copolymer is 50-70 wt % of the composition; the combination of the second siloxane-oxyalkylene copolymer, the third siloxane-oxyalkylene copolymer and dipropylene glycol is 10-20 wt % of the composition; and the methyl ester of rapeseed oil is 20-30 wt % of the composition.